Freeze eventbus dictionaries (#22628)

* Freeze event bus

* Cleanup

Content.Server/Afk/AfkManager.cs

@@ -4,7 +4,6 @@ using Robust.Server.Player;
 using Robust.Shared.Configuration;
 using Robust.Shared.Console;
 using Robust.Shared.Enums;
-using Robust.Shared.Input;
 using Robust.Shared.Player;
 using Robust.Shared.Timing;
 
@@ -35,7 +34,6 @@ namespace Content.Server.Afk
     [UsedImplicitly]
     public sealed class AfkManager : IAfkManager
     {
-        [Dependency] private readonly IEntityManager _entityManager = default!;
         [Dependency] private readonly IPlayerManager _playerManager = default!;
         [Dependency] private readonly IGameTiming _gameTiming = default!;
         [Dependency] private readonly IConfigurationManager _cfg = default!;